This document discusses various aspects of treating young permanent teeth with immature roots, including their development, characteristics, and treatment considerations. It begins by defining young permanent teeth as those recently erupted where root development is incomplete. It notes the importance of preserving these teeth due to their role in alveolar growth. The document then covers evaluation methods that are more accurate for immature teeth compared to typical pulp testing. It discusses various treatment options for both vital and non-vital pulp therapy aimed at maintaining the tooth. A brief history of pulp capping techniques is also provided.

1. PRESENTED BY : SHRIYAM SHARAN
HOD : DR MOUSUMI GOSWAMI

2. Despite of the modern
advances in prevention of
dental caries and an increased
understanding of importance
of maintaining the natural
dentition, many teeth are still
lost prematurely
The primary object of pulp
treatment of an affected tooth
is to maintain the integrity and
health of oral tissue

3. Young permanent teeth are those recently erupted teeth in
which normal physiological apical root closure has not
occurred.
Normal physiological root closure of permanent teeth may take
2-3 years after eruption.
Young permanent teeth are in developmental stage in children
from 6 years of age until mid-teens
Human tooth with immature apex is a developing organ. The
proliferation and differentiation of various cells are activated
especially in the apical region of the young tooth to make it
complete .

4.  Developing teeth are essential for development and growth
of alveolar process and periodontal ligament.
 Human tooth with immature apex is a precious tissue source
for the research of human adult stem cell
Shigehiro Abe et al, Oral Science International Journal, May 2007
 Young permanent teeth possesses a greater potential to
rebuild the host pulp tissue and continue root maturation
Granhoss et al, Journal of dental research, 2002

5.  A population of mesenchymal stem cells (MSCs) residing in the apical
papilla of incompletely developed teeth, termed stem cells from the
apical papilla (SCAP), can differentiate into odontoblast-like cells and
produce dentin-like tissue in both in vitro and in vivo study systems:
Huang G, Journal of Dentistry, 2008
 Auto transplantation of immature teeth have high success rate of survival
Wim Laurey et al, American Journal of Dentofacial Orthopaedics
 Measurement of open apices of teeth can be used to assess
chronological age
Cameriere R, Ferrante L, Cingolani M. Age estimation in children by
measurement of open apices in teeth. Int J Legal Med. 2006 Jan;120(1):49-52.
Epub 2005 Nov 10.
Shrestha et al Measurement of open apices in teeth for estimation of age in
children Health Renaissance 2014;12(1):33-37

6.  Evaluation of pulp vitality is an important diagnostic aspect of treating
young permanent teeth.
 The methods mainly used are thermal and electrical testing which test the
vitality based on the neural response of the pulp.
 Immature permanent teeth are not fully innervated with alpha- myelinated
axons: the neural components responsible for the pulpal pain response.
 This reduced number of pain receptors make them less responsive to stimuli
giving FALSE NEGATIVE results from thermal and electric pulp testing.
 Hence the need for using methods that test the circulation of the pulp
including laser Doppler flowmetry, pulsoximetry, dual wave
spectrophotometry and plethysmography.

7. ERUPTION OF YOUNG PERMANENT TEETH
 A smooth exchange from the primary to permanent dentition is of
utmost importance.
 Ectopic eruption of permanent teeth may cause disturbance in
occlusion.

8. First molar eruption: In majority of
children, the first permanent molars
erupt prior to the central incisors. The
first molar is guided into occlusion by
the distal surface of the 2nd primary
molar
Incisor eruption: The mandibular
central incisors are the first to erupt
and maxillary laterals the last.
Second molar eruption: The
mandibular 2nd molar erupts before
the maxillary 2nd molar; if otherwise,
it can lead to Class II malocclusion.
As the permanent incisors erupt, the arch width increases slightly, the
permanent incisor tips mesially and the primary cuspids move distally

9.  Numerous factors can affect the pulpal health of teeth, but the
two major conditions detrimental to young permanent teeth are
 deep caries and
 traumatic injuries.
 These often lead to pulp necrosis and arrested tooth
development of the involved immature tooth.
 The resulting wide-open apical foramina, canals with reverse
taper (blunderbuss) and thin dentinal walls, represent major
clinical concerns when an incompletely developed tooth fails to
mature.

10. These can be of two configurations
- non-blunderbuss
- blunderbuss
NON –BLUNDERBUSS
The walls of the canal may be parallel to slightly convergent as
the canal exits the root -the apex, therefore can be broad or
tapered
BLUNDERBUSS
The word ‘blunderbuss’ basically refers to an 18th century
weapon with a short and wide barrel. It derives its origin from
the Dutch word ‘DONDERBUS’ which means ‘thunder gun’.
The walls of the canal are divergent and flaring, more especially
in the buccolingual direction - The apex is funnel shaped and
typically wider than the coronal aspect of the canal.

11. Incomplete development: The open apex typically occurs when
the pulp undergoes necrosis as a result of caries or trauma,
before root growth and development are complete (i.e. during
stages 1-4)
An open apex can also occasionally form in a mature apex
(stage 5) as a result of
 Extensive apical resorption due to orthodontic treatment,
periapical pathosis or trauma
 Root end resection during periradicular surgery
 Over-instrumentation

12. According to the width of the apical foramen and the length of the root,
Cvek has classified 5 stages of root development.
 Stage 1 Teeth with wide divergent apical opening and a root length
estimated to less than half of the final root length.
 Stage 2 Teeth with wide divergent apical opening and a root length
estimated to half of the final root length.
 Stage 3 Teeth with wide divergent apical opening and a
root length estimated to two thirds of the final root
length.

13.  Stage 4 Teeth with wide open apical foramen and nearly completed root
length.
 Stage 5 Teeth with closed apical foramen and completed root
development.

16. Clinical examination
Carious involvement of pulp may be clinically obvious
Sensitivity to explorer probing, review of radiographs and
clinical excavation can confirm a suspicion that the lesion is
more advanced than it appears.
Traumatised teeth may show evidence of injury in many
ways.
With some injuries, the effect on the pulp may be neither
apparent nor diagnosable initially.
With severe injuries, the pulp is almost always deleteriously
affected and requires immediate or subsequent treatment

17. Clinical Diagnostic Procedures
 Heat, cold and electrical pulp testing are classic tests for pulpal
tests, vitality and viability.
 Interpretation of testing data must be cautious, because an
open apex provides a significantly enlarged vascular supply
but an incompletely developed nervous innervation.
(Bernick,1964)
 In traumatised teeth esp., the reactions to pulp test should not
be treated literally because the pulp is in a state of shock for
many days or weeks and may register negatively to tests and
then return later to normal status.
 Tests of mobility and percussion sensitivity should also be

18. Radiographic examination

19.  A suggested outline for determining the pulpal status of cariously
involved teeth in children involves the following:
 Visual and tactile examination of carious dentin and associated
periodontium
 Radiographic examination of
• periradicular and furcation areas
• pulp canals
• periodontal space
• developing succedaneous teeth
 History of spontaneous unprovoked pain
 Pain from percussion
 Pain from mastication
 Degree of mobility
 Palpation of surrounding soft tissues
 Size, appearance, and amount of hemorrhage associated with pulp
exposures

21. Pulp treatment modalities can be
classified into 2 categories
• Vital Pulp Therapy
1. Protective base
2. Indirect pulp capping
3. Direct pulp capping
4. Pulpotomy
5. Apexogenesis/ maturogenesis
6. Regeneration
Non vital pulp therapy:
Apexification; pulpectomy and root
filling
AAPD guidelines 2014

23. HISTORY OF PULP TREATMENT
Dentists for a long time have believed the
pulp to be capable of healing.
The first mention of pulp capping is found
in 1756 when Philip Pfaff' attempted to
cap exposed pulps with a small piece of
gold carefully adapted to the base of the
cavity.
In 1826 Leonard Koeker cauterized the
exposed portion of the pulp with a red hot
iron wire, then covered the exposure with
a piece of lead foil.
Pfaff, P.: Abhandlung von den Zaehnen des menschlichen Koerpers und deren Krank-
heiten, Berlin, 1756..
Koeker,L.: PrinciplesofDentalSurgery,London,1826,Underwood,p.433-437.

24. HISTORY OF PULP TREATMENT
Since this date there have been virtually
as many technics of pulp capping as
dentists.
The earliest attempts to promote pulp
healing consisted of placing different
metallic foils against the site of the
exposure.
Pfaff, P.: Abhandlung von den Zaehnen des menschlichen Koerpers und deren
Krank- heiten, Berlin, 1756.
Koeker,L.: PrinciplesofDentalSurgery,London,1826,Underwood,p.433-437.

25. HISTORY OF PULP TREATMENT
Among the materials recommended to promote
healing of accidental and pathological exposures of
pulp were the following: asbestos, plaster of Paris,
powdered ivory, tissue paper (and) Canada balsam,
aseptic sponge, vulcanized rubber, court plaster,
gutta percha, cork, quil, oiled silk, gall nuts,
beeswax, pulverized glass, zinc oxychloride
cements, collodion, boracic acid, iodoform powder,
iodoformagen, formaldehyde, lactophosphate of
lime, borax, zinc oxide, zinc oxide eugenol, zinc
oxide and thymol, Ca3(PO4), and eugenol,
(aCO(),CaF., Ca:(P04)2,AMg3(PO.1). and eugenol,
Ca(OH)2 and eugenol, AgLO() , Ca F'., and water,
and zinc phosphate cements.
The use of drugs and other materials in close contact with the pulp gradually came
into widespread use.

26. Vital pulp therapy for teeth diagnosed with a normal pulp or
reversible pulpitis according to AAPD
PROTECTIVE LINER
A protective liner is a thinly-applied liquid placed on the pulpal
surface of a deep cavity preparation, covering exposed dentin
tubules, to act as a protective barrier between the restorative
material or cement and the pulp.
The liner must be followed by a well-sealed restoration to
minimize bacterial leakage from the restoration-dentin interface.

27. INDICATIONS:
In a tooth with a normal pulp, when caries is removed
for a restoration, a protective liner may be placed in
the deep areas of the preparation to
 minimize pulp injury,
 promote pulp tissue healing, and
 to minimize postoperative sensitivity.
OBJECTIVES:
Tooth’s vitality,
Pulp tissue healing
Tertiary dentin formation
MATERIALS : calcium hydroxide, dentin bonding agent, or
glass ionomer cement

28. INDIRECT PULP CAPPING
Indirect pulp capping is defined as a procedure where in small
amount of carious dentin is retained in deep areas of cavity to
avoid exposure of pulp , followed by placement of a suitable
medicament and restorative material that seal off the carious
dentin and encourages pulp recovery ( INGLE )
A procedure in which only the gross caries is removed from the
lesion and the cavity is sealed for a time with a biocompatoble
material ( McDonald )
In 1961 Damle SG termed IPC as “Reconstructed dentin to
prevent pulp exposure “

29. INDICATION
HISTORY CLINICAL
EXAMINATION
RADIOGRAPHIC
EXAMINATION
• Mild pain associated
with eating
• Negetive history of
spontaneous ,
extreme pain.
• Deep carious lesion,
which are close to,
but not involving the
pulp in vital primary
or young permanent
teeth
• No mobility
• When pulp
inflammation is seen
as normal and there
is a definitive layer of
affected dentin after
removal of infected
dentin
• Normal lamina dura
& PDL space
• No radiolucency in
the bone around the
apices of the roots or
in the furcation .

30. CONTRA INDICATION
HISTORY CLINICAL
EXAMINATION
RADIOGRAPHIC
EXAMINATION
• Sharp, penetrating
pain that persists
after withdrawing
stimulus
• . Prolonged
spontaneous pain,
particularly at night
• Excessive tooth
mobility .
• Parulis in the gingiva
approximating the
roots of the tooth
• Tooth discoloration
• Non responsiveness
to pulp testing
techniques
• Large carious lesion
with apparent pulp
exposure
• Interrupted or
broken lamina dura..
• Widened periodontal
ligament space
• Radiolucency at the
root apices or
furcation areas

31. RATIONALE
• Establishment of a healthy intact pulp is desirable over
partial or complete surgical removal
• Affected pulpal tissue, in the absence of a continued insult,
is able to heal it self .

32. TREATMENT PROCEDURE
• In recent years, rather than complete the caries removal in
two appointments, the focus has been to excavate as close
as possible to the pulp, place a protective liner, and restore
the tooth without a subsequent reentry to remove any
remaining affected dentin. ( AAPD)
• Therefore single session is preferred over two
appointment procedure.

33. Single appointment procedure
Use local anesthesia & isolation with
rubber dam
Establish cavity outline with high speed
handpiece
Remove all caries using caries detector
dye .i.e infected dentin has to be
removed
Stop the excavation as soon as the firm
resistance of sound dentin is felt
If there is a probablity of exposure while
removing further caries then a consevative
approach is chosen by placing a hard set
CaOH& temporizing the tooth

34. Remaining cavity is filled with reinforced
ZOE cement
Site is covered with Ca(OH) 2
Cavity is flushed with saline & dried with
cotton pellet

35. Two appointment procedure
2nd appointment ( 6-8 weeks later)
NEGETIVE HISTORY &
INTACT TEMPORARY
RESTORATION
Reparative
dentin bridge
formed -
permanent
restn
But if caries remains on
re-entering , must be
removed carefully
The area around the
potential exposure will
appear whitish & may be
soft , which is predentin
– DO NOT DISTURB THAT
THE CAVITY
PREPARATION IS
WASHED OUT &
DRIED GENTALY
COVER THE ENTIRE
FLOOR WITH
CA(OH)2
Base is built up with ZOE or
GIC
FINAL RETORATION IS THEN
PLACED

36. DIRECT PULP CAPPING
When a small exposure of the pulp is encountered
during cavity preparation and after hemorrhage
control is obtained, the exposed pulp is capped
with a material such as calcium hydroxide or MTA
prior to placing a restoration that seals the tooth
from microleakage.
INDICATIONS: Direct pulp capping is indicated for
a permanent tooth that has a small carious or
mechanical exposure in a tooth with a normal pulp.

37. OBJECTIVES:
• To maintain vitality of tooth
• To create new dentin in the area of the
exposure and subsequent healing of pulp.
Contra indication
• Severe tooth ache at night
• Spontaneous pain
• Tooth mobiity
• Radiographic appearance of pulp rperiradicular degeneration
• Excess of hemorrhage at the time of exposure
• internal nad external root resorption
• Swellinfgand fistula

38. Technique
Final restoration is done after determining the success of
pulp capping
Place temporary restoration
Place the pulp capping material on the exposed pulp with
application of minimal pressure so as to avoid forcing the
material into pulp chamber
Haemorrhage is arrested with light pressure from sterile
cotton pellet
Cavity should be irrigated

39. After 24 hours : necrotic zone
adjacent to calcium hydroxide paste
is separated from healthy pulp tissue
by adeep staining basophilic layer
After 7 days : increase in
cellular & fibroblastic
activity
After 14days ; partly
calcified fibrous
tissue lined by
odontoblastic cells
is seen below
calcium protienate
zone , dis apearance
of necrotic zone
After 28 days
: zone of new
dentin

40. Calcium Hydroxide
Bio dentine
Bio aggregates
Mineral Trioxide Aggregate (MTA)
Alpha-Tricalcium
Phosphate
Resin Bonding agents
Laser
Glass ionomers cement
Collagen
Corticosteroids & antibiotics
Isobutyl cyanoacrylate
Bone morphogenic
protein
Theracal
Various materials used for DPC

41. Pulpotomy
Partial pulpotomy for carious exposures.
The partial pulpotomy for carious exposures is a procedure
in which the inflamed pulp tissue beneath an exposure is
removed to a depth of one to three millimeters or deeper to
reach healthy pulp tissue.
INDICATIONS: A partial pulpotomy is indicated in a young
permanent tooth for a carious pulp exposure in which the pulpal
bleeding is controlled within several minutes. e tooth must be
vital, with a diagnosis of normal pulp or reversible pulpitis

42. OBJECTIVES:
• The remaining pulp should continue to be vital after
partial pulpotomy.
• There should be no adverse clinical signs or symptoms
such as sensitivity, pain, or swelling.
• There should be no radiographic sign of internal or
external resorption, abnormal canal calcification, or
periapical radiolucency postoperatively.
• Teeth having immature roots should continue normal
root development and apexogenesis.

43. Partial pulpotomy for traumatic exposures (Cvek pulpotomy).
The partial pulpotomy for traumatic exposures is a
procedure in which the inflamed pulp tissue beneath an
exposure is removed to a depth of one to three millimeters
or more to reach the deeper healthy tissue.
INDICATIONS:
• This pulpotomy is indicated for a vital, traumatically-exposed, young
permanent tooth, especially one with an incompletely formed apex.
• Pulpal bleeding after removal of inflamed pulpal tissue must be controlled.
• Neither time between the accident and treatment nor size of exposure is
critical if the inflamed superficial pulp tissue is amputated to healthy pulp.

44. PROCEDURE
After anesthesia and rubber dam isolation, complete
excision of carious tissue is performed with a high-
speed handpiece
The pulp chamber roof is the removed and the pulp
content entirely eliminated using a low-speed
handpiece under spray or a sharp excavator.
The cavity is rinsed then dried with cotton pellets
Hemostasis is obtained by compressing the cotton
pellets the fixative agent against the pulp stumps in
the canal entrances.

45. Hemostasis is normally performed in 4-5 minutes.
Failure to achieve it in on time is a sign that
inflammation is deeper than suspected. The tooth
is not treatable by pulpotomy and the only
remaining therapeutic option is pulpectomy.
When the cotton pellet is removed, tissues
should be brownish without signs of bleeding.
Zinc-oxide eugenol cements can be used to seal
the entrances, covered by a glass-ionomer filling.
After setting, either amalgam or composite
materials can be used to restore the tooth.

46. MATERIALS
Formocresol : Many agents were used in pulpotomy procedures and
formocresol was by far the most popular due to its ease of use and
excellent clinical results, although longitudinal studies have reported
that the clinical success of formocresol pulpotomies decreased with
time and that histologic response of the pulp was variable ranging from
chronic inflammation to necrosis .
Other concerns were regarding systemic distribution,12 potential
toxicity, allergenicity, carcinogenicity, and mutagenicity of
formaldehyde led to seeking alternatives to this product

47. Among these alternatives glutaraldehyde ,electrosurgery,
laser,ferric sulfate,collagen,freeze- dried bone, morphogenetic
bone proteins, and MTA (Mineral Trioxide Aggregate).

48. Apexogenesis (root formation) : Apexogenesis is a histological term used to
describe the continued physiologic development and formation of the root’s
apex.
Formation of the apex in vital, young, permanent teeth can be accomplished by
implementing the appropriate vital pulp therapy ie,
 indirect pulp treatment,
 direct pulp capping,
 partial pulpotomy for carious exposures and traumatic exposures
APEXOGENESIS & MATUROGENESIS
Maturogenesis is a recent attractive term that has been
defined as physiologic root development, not restricted to the
apical segment. The continued deposition of dentin occurs
throughout the length of the root, providing greater strength
and resistance to fracture

49. • If normal pulp tissue with minimal inflammation is present,
normal root end development occurs
However, in immature teeth with pulp necrosis and
bacterial infection, the long-term prognosis is related to
the stage of root development and the amount of root
dentine present at time of injury.

50. Rationale
• Poor long-term prognosis of endodontically treated
immature teeth
Relatively thin dentine in obturated canal of incompletely
formed roots and open apices are at risk of fracture
• pulp revascularization and repair will more readily occur in
teeth with a wide apical foramen
• pulp of immature teeth has a significant repair potential

51. Indication
traumatic luxation
fractured tooth with pulpal exposure
carious exposures

52. Goals
• Sustaining a viable Hertwig’s sheath to allow continued
development of root length for favourable crown:root ratio
• Treatment strategies of traumatized, immature permanent
teeth should aim at preserving pulp vitality to secure
further root development and tooth maturation.
• Promoting a root end closure
• Generating dentinal bridge at the site of pulpotomy

53. Procedure
Remove all the caries tooth and open up the
pulp chamber
Remove coronal pulp tissue with excavator,
prevent damage to the radicular pulp
Rinse all the residual debrise & control
hemorrhage by place ment of a moist cotton
pellet over the amputed pulp
CaOH mixture is placed over the pulp stums,
followed by temporary restoration
Follow up radiographs are taken and once the
root development is complete the
conventional RCT is done.

54. Keep the Pulp
ALIVE!!

55. REGENERATIVE ENDODONTICS:
“Biologically based procedures designed to replace
damaged structures, including dentin and root
structures, as well as cells of the pulp-dentin complex
.”
Cohen 10th edition

56. Historical development
of the field
• Nygard –OstbyB: The role of blood clot in endodontic therapy:an experimental
histologic study. Acta Odontol Scand 19:323,1961
• Nygard- Ostby B:Tissue formation in the root canal following pulp removal.
Scand J DENT RES 79:333,1971
The foundation of regenerative endodontics was laid when Nygaard-Østby in
1961 evoked intracanal bleeding in mature teeth diagnosed with either vital or
necrotic pulp that received root canal therapy
kloroperka obturation was placed coronal to the formed blood clot
Follow up : 17 days to 3.5 years

57. The treated tooth was extracted and the newly formed tissues were
examined histologically.
The outcomes were similar for all teeth:
(i) resolution of symptoms of inflammation related to foraminal
enlargement and over-instrumentation in as early as 17 days
(ii) resolution of signs and symptoms of pathosis for the necrotic cases
(iii) In certain cases, radiographic evidence of apical closure.
From the histological analysis, it was observed that there was
ingrowth of connective tissue into the canal space and varied levels
of mineralized tissue along the canal walls as well as “islands” of
mineralized tissue embedded within the newly formed tissue.
However, the inclusion of undesired cell types (e.g. cementoblasts)
and the lack of desired cell types (e.g. odontoblasts) indicate that this
protocol did not lead to complete histological regeneration of dental
pulp.

58. Potential methods for regenerating an entire
tooth (Nakhara et al.)
The first approach:
Seeding appropriate stem cells onto scaffolding materials with
the addition of specific growth factors and/or signalling
molecules.
The second approach:
Replicating the natural developmental processes of embryonic
tooth formation. Artificial tooth germs are transplanted into
the bodies of animal hosts where there is enough blood flow to
support tissue formation.

59. Alternative
 Regenerate a functional pulp-dentin complex within a
patient's existing permanent tooth to restore natural
functions and neural sensation.
 From a tissue engineering perspective the dental pulp is a
comparatively easier tissue to regenerate
Although either approach may evolve into a method
capable of generating entire teeth, the natural
development of permanent human teeth takes years to
complete. Regenerating an entire tooth from a
patient's own stem cells may not be clinically practical.

60. Triad of Regenerative Endodontics
Regenerative
Endodontics
Control of
inflammation
Stem cellBiomaterials
Nadia Chugal, Louis M. Lin, and Bill Kahler

61. The major domains of research required to
develop regenerative endodontic procedures.
(Peter E. Murray et al)

62. Stem cells
Stem cells
Adult /Postnatal
Embryonic/Fetal
A stem cell is commonly defined as a cell that has the ability to
continuously divide and produce progeny cells that differentiate
into various other types of cells or tissues

63. Adult Stem cells
Type
• Totipotent
• Pluripotent
• Multipotent
Cell plasticity
• Each cell can develop into
a new individual
• Cell can form any cell type
(over 200
• Cell differentiated but can
form a number of other
tissues
Source of stem
cell
• 1-3 days of
embroyonic life
• 5-14 days of
embryonic life
• Fetal tissue, cord
blood, and postnatal
stem cells including,
dental pulp stem cells
Autogenic, Allogenic and Xenogenic stem cells

64. 2. Growth factors
• Growth factors are proteins that bind to receptors on the cell and
induce cellular proliferation and/or differentiation
GF + Stem cells = increased prolifereation & differentiation
For e.g.
• TGF Beta and Recombinant human BMP2 stimulates differentiation
of adult pulp stem cells into an odontoblastoid morphology
(Roberts-Clark DJ, Smith AJ. Angiogenic growth factors
in human dentine matrix. Arch Oral Biol 2000;45:1013–
6)

65. • Recombinant BMP-2, -4, and -7 has shown to induce
formation of reparative dentin in vivo
( Nakashima M, et al. Regulatory role of transforming growth factor-beta, bone morphogenetic
protein-2, and protein-4 on gene expression of extracellular matrix proteins and differentiation of dental
pulp cells. Dev Biol 1994;162:18 –28.)
• The application of recombinant human insulin-like
growth factor-1 together with collagen has been found to
induce complete dentin bridging and tubular dentin
formation .
(Lovschall H, Fejerskov O, Flyvbjerg A. Pulp-capping with recombinant human insulin-like growth
factor I (rhIGF-I) in rat molars. Adv Dent Res 2001;15:108 –12)
This indicates the potential of adding growth factors in
regenerative endodontics and also before pulp capping to
stimulate dentin and pulp regeneration.

66. Scaffolds
• For tissue engineering therapy, pulp stem cells must be
organized into a 3 dimensional structure that can
support cell organization.
• It can be achieved using a porous polymer scaffold
seeded with pulp stem cells

67. • Scaffolds are three-dimensional (3D) porous solid
biomaterials designed which
1. Provide a spatially correct position of cell location
2. Promote cell-biomaterial interactions, cell adhesion, and
matrix deposition
3. Permit sufficient transport of gases, nutrients, and
regulatory factors to allow cell survival, proliferation, and
differentiation
4. Biodegrade at a controllable rate that approximates the
rate of tissue regeneration
5. Provoke a minimal degree of inflammation or toxicity in
vivo.

68. • Ideal requirements of a scaffold
1. A high porosity and an adequate pore size are necessary to
facilitate cell seeding and diffusion throughout whole
structure of both cells and nutrients
2. Should allow effective transport of nutrients, oxygen, and
waste
3. Biodegradability is essential, since scaffolds need to be
absorbed by the surrounding tissues without the necessity
of surgical removal.
4. The rate at which degradation occurs has to coincide with
the rate of tissue formation.
5. Should be biocompatible.
6. Should have adequate physical and mechanical strength.

69. Types of scaffolds:
Scaffolds
Natural.
(Derivatives of
extracellular matrix)
Synthetic
(Polyster)

70. Attributes of commonly used scaffold

71. Correct delivery of appropriate stem cells and growth
factors embedded within a scaffold
Stem
cells
Growth
factors
Scaffold
If one were to inject cells along the entire coronal-apical extent
of a root canal system, the vast majority of cells would be
expected to succumb to tissue hypoxia.
One alternative approach would be to inject a
cell/scaffold/growth-factor mixture into the apical 1 mm of the
root canal system and then “back-fill” the root canal system
with a scaffold/growth-factor combination.

73. Potential Technologies for Regenerative
Endodontics
1. Root Canal Revascularization via Blood Clotting
2. Postnatal Stem Cell Therapy
3. Pulp Implantation
4. Injectable Scaffold Delivery
5. Gene Therapy
6. Three-Dimensional Cell Printing

74. Apexification
with calcium
hydroxide
Long time span of the entire treatment
Multiple visits
Increased risk of tooth fracture due to long-term
application of Ca(OH)2
Apexification
with MTA
One- or two-step apexification
Neither strengthens the root nor promotes further
root development
Roots remain thin and fragile
Revascularizat
ion
Promotes further root development
Causes reinforcement of dentinal walls by
deposition of hard tissue (strengthening the root
against fracture)
The characteristics of three treatment procedures for
immature root formation

75. • Pulp revascularization = induction of angiogenesis in
endodontically-treated root canal
• Pulp regeneration = pulp revascularization +
restoration of functional odontoblasts and/or nerve
fibers

76. • “To date, no published clinical trials have fully incorporated
the tissue-engineering concepts. Instead, studies over the last
50 years have focused on revascularization techniques, which
share some features with the principles of regenerative tissue
engineering.” (Cohen 10th edition.)
• The key distinction is that in contrast to the focused delivery
of cells/growth factors/scaffolds employed in tissue-
engineering approaches, revascularization focuses on
triggering bleeding into an empty root canal space with the
hope that this will trigger a process similar to the role of the
blood clot in triggering wound healing in surgical procedures

78. Case selection
• “This treatment should be considered for the incompletely
developed permanent tooth that has an open apex and is
negative to pulpal responsiveness testing. Although the
ultimate goal of this approach is to develop a tissue
engineering–based method of pulpal regeneration in the
fully developed permanent tooth, it should be recognized
that current revascularization protocols have not been
developed or evaluated for these more challenging cases.”
Cohen10thedition

79. During the first appointment
• Minimal instrumentation by the use of a small file
(determine the working length)
• Copious and slow irrigation with 20 ml of NaOCl (lower
concentration) followed by 20 ml of 0.12% to 2%
chlorhexidine (CHX), slow irrigatin with closed end side
vented needle kept at the apex .
• The root canal system is then dried with sterile paper
points, and the antimicrobial medicament is delivered into
the root canal space.
,

80. • The best available evidence supports the use of either a triple
antibiotic paste or Ca(OH)2. Both medicaments have been
shown to be effective .
• Place antibiotic paste or calcium hydroxide.
If the triple antibiotic paste is used:
 1) consider sealing pulp chamber
with a dentin bonding agent to minimize risk of staining
and
 2) mix 1:1:1 ciprofloxacin :metronidazole : minocycline
(or, if esthetics are crucial, then consider a 1:1 mixture
of ciprofloxacin and metronidazole)
• Deliver into canal system via Lentulo spiral, MAP system
or Centrix syringe

81. If triple antibiotic is used, ensure that it remains below CEJ
( to minimize crown staining).
Seal with 3‐4mm Cavit, followed by IRM, glass ionomer
cement or another temporary material
Dismiss patient for 3‐4 weeks

82. Second Appointment
Assess response to initial treatment.If there are signs
symptoms of persistent infection, consider additional treatment with t
he antimicrobial, or an alternative
antimicrobial. Recall the patient in about 3‐4 weeks as before.
Anesthesia with 3% mepivacaine without vasoconstrictor, rubber d
am, isolation
Copious, slow irrigation with 20ml 17% EDTA, followed by norma
l saline, using a similar closed end needle.
Dry with paper points.

83. • Create bleeding into canal system by over‐instrumenting (endo
file, endo explorer)
• Stop bleeding 3mm from CEJ
• Place CollaPlug/Collacote at 3mm below CEJ.
• Place 3‐4mm of a MTA and reinforced glass ionomer and place p
ermanent restoration.

84. • Follow‐up
Clinical and Radiographic exam:
• No pain or soft tissue swelling (often observed between first
and second appointments)
• Resolution of apical radiolucency (often observed 6‐12
months after treatment)
• Increased width of root walls (this is generally observed
before apparent increase in root length and often
occurs 12‐24 months after treatment)
• Increased root length

86. Medicaments being used in cases of
revascularization
1. Triple antibiotic paste (1 : 1 : 1 mixture of
ciprofloxacin/metronidazole/minocycline)
2. Ca(OH)2 alone or in combination with antibiotics,
3. Formocresol

87. 1. The triple antibiotic paste produced significantly greater differences
in dentinal wall thickness compared with either the Ca(OH)2 or
formocresol groups.
2. The formocresol group showed the smallest improvement in root
length and thickness.
3. Location of Ca(OH)2 placement appeared to be a strong predictor
of radiographic outcome.
4. When Ca(OH)2 placement was restricted to the coronal half of the
root canal, the increase in root wall thickness was 55%, compared
to a 3% increase when it was placed in the apical half of the root
canal system. This might be due to residual Ca(OH)2 having a
cytotoxic interaction with stem cells
Bose R, Nummikoski P, Hargreaves K: A retrospective evaluation of radiographic outcomes
in immature teeth with necrotic root canal systems treated with regenerative endodontic
procedures. J Endod 35:1343, 2009.

88. Clinical Measures of Treatment Outcome
• The goal of revascularization extends beyond non
surgical root canal treatment
• For regeneration not only radiographic evidence of
periradicular health but also radiographic and other
clinical evidence of functioning vital tissue in the canal
space is required.
• Radiographic evidence of functioning pulp (or pulp
like) tissue would include continued root growth, both
in length and wall thickness.

89. • Other measures of the presence of vital, functioning
tissue in the canal space include laser Doppler blood
flowmetry, pulp testing involving heat, cold, and
electricity and lack of signs or symptoms.
• “ The ideal clinical outcome is an asymptomatic tooth
that does not require retreatment, but to validate that
regenerative endodontic techniques are truly
effective, nonsubjective vitality-assessment methods
are essential”

90. Advantages of revascularization
Traditionally an immature tooth with open apex is treated by apexification:
1. Calcium hydroxide : short-term or long-term use of Ca(OH)2 can
reduce root strength. A large case series using the traditional
apexification protocol showed that a major reason for tooth loss
following apexification was root fracture.
Cvek M: Prognosis of luxated non-vital maxillary incisors treated with calcium hydroxide and filled with gutta-percha. A
retrospective clinical study. Endod Dent Traumatol 8:45, 1992
2. MTA : one step apexification , however does not result in further root
development.
In contrast in revascularization there is a greater likelihood of increase in root wall
length and thickness.

91. • This approach is technically simple and can be
completed using currently available instruments and
medicaments without expensive biotechnology.
• The regeneration of tissue in root canal systems by a
patient’s own blood cells avoids the possibility of immune
rejection and pathogen transmission from replacing the
pulp with a tissue engineered construct.

92. LIMITATIONS
• The source of the regenerated tissue has not been identified
• Relys on blood clot formation but the concentration and
composition of cells trapped in the fibrin clot is unpredictable.
• Enlargement of the apical foramen is necessary to promote
vascularizaton and to maintain initial cell viability via nutrient
diffusion. It is likely that cells in the coronal portion of the root
canal system either would not survive or would survive under
hypoxic conditions

95. APEXIFICATION
It is defined as method to induce development of the
root apex of an immature pulpless tooth by formation
of osteocementum/ bone like tissue ( COHEN) .
It is a method of inducing apical closure by formation of a
mineralized tissue in the apical region of a non vital
permanent tooth with an incompletely formed root apex.

96. INDICATIONS: This procedure is indicated for non-vital
permanent teeth with incompletely formed roots.
OBJECTIVES:
 This procedure should induce root end closure (apexi cation) at the apices of
immature roots or result in an apical barrier as confirmed by clinical and
radiographic evaluation.
 Adverse post-treatment clinical signs or symptoms of sensitivity, pain, or
swelling should not be evident.
 There should be no radiographic evidence of external root resorption, lateral
root pathosis, root fracture, or break- down of periradicular supporting tissues
during or following therapy.
 The tooth should continue to erupt, and the alveolus should continue to grow in
conjunction with the adjacent teeth.

97. MATERIALS USED
• Zinc oxide eugenol
• Metacresylacetate –comphorated paracholorophenol
• Tricalciumphosphate + beta tricalcium ohosphate
• Resorbable tricalcium phosphate
• Collagen calcium phosphate gel calcium hydroxide
• Mineral trioxide aggregate
• The factors most responsible for apical closure are thorough débridement &
coronal seal.
• Causes of failure: bacterial contamination.
• Apexification involves cleaning & shaping, followed by placement of Ca(OH)2
or MTA to the apex.

98. Technique
Temporary restoration.
Effective temporary seal between visits is critical.
Place Ca(OH)2 2mm short of radiographic apex
Establish the working length of canal, BMP of canal should be done
Extirpate the pulp tissue remnants from the canal and irrigate it with saline.
Gain staight line access to canal orifice
Anaesthesize the tooth and isolate it with rubber dam

99. Repeat the process if no satisfactory result found
Treatment time from 6 wks to 18 months
Confirm the Progress of apexification by passing an
instrument through the apex after removal of calcium
hydroxide
Patient is again recalled and examined for radiographic
evidence of root formation
Second visit at 3 months for monitoring the tooth. If
symptomatic; canal is cleaned and again filled with
calcium hydroxide

101. Ca(OH)2
Advantages
1) alkaline pH
2) bactericidal
3) stimulate apical calcification.
Note: The reaction of periapical tissues to Ca(OH)2 is
similar to that of pulp tissue.
Ca(OH)2 produces a multilayered sterile necrosis
permitting subjacent mineralization.

102. Ca(OH)2
disadvantages
1) long treatment period, usually takes 6-9 months, &
may extend up to 21 months.
2) must be replaced at monthy intervals & removed some
months after placement
before final obturation.
3) multiple visits by the patient.
4) possible recontamination may occur.
5) weaken the root dentin & the risk of teeth fracture.

103. •Ca(OH)2
• Mechanism of mineralization induced by Ca(OH)2
• * Calcium ions dissociated from Ca(OH)2 are
critical for inducing the mineralization of
osteoblasts.
• * Hydroxyl ions did not have any effect on the
mineralization.
• * The mineralization activity of Ca(OH)2 was
higher at pH 7.4 than at pH 8.5. Mineralization
activity was higher under neutral conditions.

104. MTA
Advantages
1) Save treatment time. High success rate. It is the material of choice for
apexification & apexogenesis.
2) Alkaline pH, which may impart antibacterial effect on some facultative
bacteria.
3) Can induce formation (regeneration) of dentin, cementum, bone &
periodontal ligament.
4) Excellent biocompatibility and appropriate mechanical properties.
5) Excellent sealing ability.
6) Produces an artificial barrier, against which an obturating material can
be condensed.
7) Hardens (sets) in the presence of moisture.
8) More radiopaque than Ca(OH)2.
9) Vasoconstrictive. This could be beneficial for hemostasis (most
importantly in pulp capping).

105. MTA
•Disadvantages
•1) Long setting time (2-4 h after mixing).
•2) Poor handling properties. The loose
sandy nature of the mixture causes
much difficulty for insertion & packing of
MTA.
•3)High cost.

106. •MTA
•Uses
• 1)Apexogenesis, direct pulp capping and
pulpotomy.
• 2)Apexification, and root-end filling.
• 3)Repair of root perforations.
• 4)Repair of internal and external resorption.

107. MTA
Composition
* MTA is mainly composed of 3 powder
ingredients, which are 75% Portland cement, 20%
bismuth oxide, 5% gypsum; lime (CaO), silica
(SiO2) are the 3 main oxides in the cement.
* Portland cement is the major constituent. It is
responsible for the setting & biologic
properties.
* Bismuth oxide provides radiopacity.
* Gypsum is an important determinant of setting
time.

108. • * Portland cement is composed of 4 major
components; tricalcium silicate, dicalcium silicate,
tricalcium aluminate, & tetracalcium aluminoferrite.
• * Tricalcium silicate is the most important constituent
of Portland cement. It is the major component in the
formation of calcium silicate hydrate which gives
early strength to Portland cement.
• * Dicalcium silicate hydrates more slowly than
tricalcium silicate & is responsiple for the latter’s
strength.
• * Aluminoferrite (contains iron) is present in gray
MTA. It is responsible for the gray discoloration. It
may discolor the tooth.

109. • Types of MTA
Gray MTA (GMTA) White MTA (WMTA)
1. Contains aluminoferrite (contains
iron), which is responsible for the gray
discoloration. It discolors both the
tooth & gingival tissue close to the
repaired root surface.
1. Tooth-colored, due to lower amounts of
Fe2O3.
2. 2. Smaller particles with narrower size
distribution (8 times smaller than that
of GMTA).
3. 3. Greater compressive strength.
4. Produces 43% more surface
hydroxyapatite crystals than WMTA in
an environment with PBS (phosphate-
buffered saline).
4.
5. Induced dentin formation more
efficiently; high number of dentin
bridge formation (reparative dentin).
5.

110. •MTA
• Reaction & formation of hydroxyapatite
• * Hydration reaction.
• * Notes: - MTA is called hydraulic silicate cement (HSC).
- It is called hydraulic cement (i.e. sets & is stable under
water) relying primarily on hydration reactions for
setting.
- The material consists primarily of calcium silicate.
• * When mixed with water, MTA sets. The pH of MTA
increases from 10 to 12.5 three hours after mixing.
In high pH environment, the calcium ions that are
released from MTA react with phosphates in the tissue
fluid to form hydroxyapatite (the principal mineral in
teeth & bones).

111. •MTA
• Manipulation
• Mixing: gray MTA & white MTA are mixed with supplied sterile
water in a powder to liquid ratio of 3:1 according to the
manufacturer’s instruction.
• Note: Poor handling properties. The loose sandy nature of the
mixture causes much difficulty for the insertion & packing of
MTA.
•
• Insertion: Ultrasonic-assisted condensation [the ultrasonic
vibration applied to endodontic plugger(condenser)] is more
efficient than hand condensation in:
- the apical flowing of MTA (enable better flow).
- delaying bacterial leakage (enable better adaptation).
- the production of denser MTA apical plug.

112. •MTA
• * Thickness: 5-mm MTA apical plug provided
reduced microleakage.
• * A Radiogragh is made.
• * A moist (wet) cotton pellet is placed above the
MTA (to ensure setting), & a well-sealing
temporary restoration is placed.
Note: MTA sets 3-4 h after mixing.
• * The patient is recalled when MTA has set (at
least 24 hours) for obturation & placement
of permanent restoration.

113. •MTA
• * Complete the root canal treatment with gatta-
percha & composite resin restoration
extending below the cervical level of the tooth
to strengthen the root’s resistance to fracture.

114. MTA procedure
Ca(OH)2 therapy done
After 1-2 week , MTA powder is mixed with
distilled water & carried into canal with
amalgam carrier & plugged apically
Apical barrier formation verified
radiographically
Wet cotton is placed over the
chamber & access cavity is
sealed with reinforced ZOE
After 2 days hardening is checked &
remaining canal is obturated with
gutta percha
Calcium hydroxide procedure
Ca(OH)2 powder is used 2mm
short of radiograph apex
Remaining canal is filled with
Ca(OH)2 & saline
A dry pledget of Ca(OH)2 is then
ejected into pulp chamber &
forced against paste ahead of it
and place temporary restoration
2nd visit after 6-24 months .
Tooth is reentered &
apexification is verified

115. Frank has described four successful results of apexification
treatments:
I. continued closure of the canal and apex to a normal
appearance,
II. a dome shaped apical closure with the canal retaining a
blunderbuss appearance,
III. no apparent radiographic change but a positive stop in
the apical area, and
IV. a positive stop and radiographic evidence of a barrier
coronal to the anatomic apex of the tooth.
Evidence of root apical closure…

116. Pulpectomy in permanent teeth is conventional root canal
(endodontic) treatment for exposed, infected, and/or
necrotic teeth to eliminate pulpal and periradicular infection.
In all cases, the entire roof of the pulp chamber is removed
to gain proper access to the canals and eliminate all coronal
pulp tissue.
Following debridement and shaping of the root canal
system, obturation of the entire root canal is accomplished
with a biologically acceptable, nonresorbable filling material.
Obturation as close as possible to the cementodentinal
junction should be accomplished with gutta percha or other
filling material acceptable.

117. Pulpectomy or conventional root canal treatment is indicated
for a restorable permanent tooth with irreversible pulpitis or
a necrotic pulp in which the root is formed fully.
There should be evidence of a successful filling without gross
overextension or under filling in the presence of a patent
canal.
There should be no adverse post-treatment signs or
symptoms such as prolonged sensitivity, pain, or swelling,
and there should be evidence of resolution of pretreatment
pathology with no further breakdown of periradicular
supporting tissues clinically or radiographically.

118. Many teeth are not given the opportunity to be saved and
instead are extracted, with subsequent placement of an
artificial prosthesis, such as an implant.
Regenerative endodontic offer an alternative method to save
teeth that may have compromised structural integrity.
CONCLUSION

119. REFERENCE
1. Cohen -10th edition
2. Shobha tondon -2nd ecition
3. Ingel –
4. Nygard –OstbyB: The role of blood clot in endodontic therapy:an
experimental histologic study. Acta Odontol Scand 19:323,1961
5. Nygard- Ostby B:Tissue formation in the root canal following pulp
removal. Scand J DENT RES 79:333,1971
6. Pfaff, P.: Abhandlung von den Zaehnen des menschlichen Koerpers und
deren Krank- heiten, Berlin, 1756.
7. Koeker,L.: PrinciplesofDentalSurgery,London,1826,Underwood,p.433-
437.
8. AAPD Guidelines 2014.